Disk drive seeding data path protection with system data seed

Abstract

A disk drive is disclosed comprising a head actuated over a disk comprising a plurality of data sectors. A redundancy generator is loaded with a first seed value corresponding to system data generated internal to the disk drive. First data path redundancy symbols are generated in response to the first seed value, and the system data and the first data path redundancy symbols are written to a first data sector. A syndrome generator is loaded with the first seed value to generate first syndromes when reading the system data and first data path redundancy symbols from the first data sector. The validity of the system data is verified in response to the first syndromes.

1. A disk drive comprising:
 a disk comprising a plurality of data sectors; 
 a head actuated over the disk; and 
 control circuitry operable to:
 load a redundancy generator with a first seed value corresponding to system data generated internal to the disk drive; 
 generate first data path redundancy symbols in response to the first seed value; 
 write the system data and the first data path redundancy symbols to a first data sector; 
 load a syndrome generator with the first seed value; 
 generate first syndromes when reading the system data and first data path redundancy symbols from the first data sector; and 
 verify the validity of the system data in response to the first syndromes. 
 
 
     
     
       2. The disk drive as recited in  claim 1 , wherein:
 the first seed value comprises a system data identifier; and 
 the control circuitry is operable to write the system data identifier to the first data sector. 
 
     
     
       3. The disk drive as recited in  claim 2 , wherein the system data identifier identifies a header data sector written to the disk to mark a beginning of a write command. 
     
     
       4. The disk drive as recited in  claim 2 , wherein the system data identifier identifies a footer data sector written to the disk to mark an end of a write command. 
     
     
       5. The disk drive as recited in  claim 1 , wherein the control circuitry is further operable to:
 load the redundancy generator with a second seed value corresponding to user data received from a host, wherein the first seed value is different than the second seed value; 
 generate second data path redundancy symbols in response to the second seed value; 
 write the user data and the second data path redundancy symbols to a second data sector; 
 load the syndrome generator with the second seed value; 
 generate second syndromes when reading the user data and second data path redundancy symbols from the second data sector; and 
 verify the validity of the user data in response to the second syndromes. 
 
     
     
       6. The disk drive as recited in  claim 5 , wherein the second seed value corresponds to a logical block address received from the host and assigned to the user data. 
     
     
       7. The disk drive as recited in  claim 5 , wherein the redundancy generator is operable to generate the first and second data path redundancy symbols according to an error detection code. 
     
     
       8. The disk drive as recited in  claim 7 , wherein the error detection code comprises a cyclic redundancy code. 
     
     
       9. A method of operating a disk drive, the disk drive comprising a head actuated over a disk drive comprising a plurality of data sectors, the method comprising:
 loading a redundancy generator with a first seed value corresponding to system data generated internal to the disk drive; 
 generating first data path redundancy symbols in response to the first seed value; 
 writing the system data and the first data path redundancy symbols to a first data sector; 
 loading a syndrome generator with the first seed value; 
 generating first syndromes when reading the system data and first data path redundancy symbols from the first data sector; and 
 verifying the validity of the system data in response to the first syndromes. 
 
     
     
       10. The method as recited in  claim 9 , wherein:
 the first seed value comprises a system data identifier; and 
 the method further comprises writing the system data identifier to the first data sector. 
 
     
     
       11. The method as recited in  claim 10 , wherein the system data identifier identifies a header data sector written to the disk to mark a beginning of a write command. 
     
     
       12. The method as recited in  claim 10 , wherein the system data identifier identifies a footer data sector written to the disk to mark an end of a write command. 
     
     
       13. The method as recited in  claim 9 , further comprising:
 loading the redundancy generator with a second seed value corresponding to user data received from a host, wherein the first seed value is different than the second seed value; 
 generating second data path redundancy symbols in response to the second seed value; 
 writing the user data and the second data path redundancy symbols to a second data sector; 
 loading the syndrome generator with the second seed value; 
 generating second syndromes when reading the user data and second data path redundancy symbols from the second data sector; and 
 verifying the validity of the user data in response to the second syndromes. 
 
     
     
       14. The method as recited in  claim 13 , wherein the second seed value corresponds to a logical block address received from the host and assigned to the user data. 
     
     
       15. The method as recited in  claim 13 , further comprising generating the first and second data path redundancy symbols according to an error detection code. 
     
     
       16. The method as recited in  claim 15 , wherein the error detection code comprises a cyclic redundancy code.